Purpose :
Both phaco/IOL and phaco/IOL + GSL have been shown to lower intraocular pressure (IOP) in patients with PACD. We conducted a trial to determine which of these procedures is more effective in lowering IOP at 1 year.

Methods :
Patients were recruited from Singapore, Vietnam, Hong Kong and Thailand. Those with PACD, IOP>21mmHg (or on IOP lowering medication), cataract and at least one quadrant of peripheral anterior synechiae (PAS) were randomly assigned to one of 2 treatment groups; phaco/IOL or phaco/IOL + GSL. GSL was performed after implantation of the intraocular lens using a direct gonioscopic lens and blunt spatula, and all PAS visible at the time of surgery was broken. Post-operative IOP medication was only allowed if IOP >21mmHg on 2 consecutive visits, excluding the first week. Success was defined as IOP ≤ 21mmHg without IOP lowering medication, and a decrease in IOP of ≥ 80% of baseline IOP, at 1 year. Chi-square or Fishers exact test statistical tests were used as appropriate to compare success between the 2 groups.

Results :
40 eyes were randomized into the phaco/IOL group and 42 to the phaco/IOL + GSL group. The mean age was 64.7 ± 8.6 and 64.4 ± 9.1 (p=0.87) respectively. There were 71 patients who reached 1 year follow up (36 in the phaco/IOL group). IOP was significantly lowered in both groups (by 27.0 ± 38.9% in the phaco/IOL and 27.6 ± 22.9% in the phaco/IOL + GSL group (p=0.45) compared to baseline IOP. Success was achieved in 16/36 (48.5%) in the phaco/IOL group and 21/34 (61.8%) in the phaco/IOL + GSL group (p=0.27). Multivariate logistic regression analysis found that only higher baseline IOP was significantly associated with success. There were no significant intra- or post-operative complications in either group.

Conclusions :
Both procedures were safe and achieved similar percentage reductions in IOP at 1 year. Success at one year was not significantly different between the groups. There is no significant advantage in performing concurrent GSL for patients with PACD undergoing phaco/IOL.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.